397
FXUS64 KLUB 250550
AFDLUB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1150 PM CST TUE FEB 24 2015
.AVIATION...
SNOW SHOWERS SHOULD CONTINUE TO SKIRT AROUND ALL TAF SITES
TONIGHT...WITH THE BRUNT OF THE ACTIVITY REMAINING OFF TO THE
SOUTH ACROSS THE PERMIAN BASIN AHEAD OF AN APPROACHING UPPER LEVEL
LOW PRESSURE SYSTEM. A WEAKER DISTURBANCE WILL PASS FARTHER NORTH
BRINGING PERHAPS FLURRIES OFF TO THE NORTH AND EAST OF KCDS. MID
CLOUDS SHOULD GIVE WAY TO A FEW CIRRUS WEDNESDAY MORNING AS WINDS
REMAIN WEST/NORTHWESTERLY AT OR BELOW 10 KNOTS. A COLD FRONT WILL
APPROACH LATER IN THE AFTERNOON...VEERING WINDS NORTHEASTERLY WHILE
INCREASING TO 12-15 KNOTS AFTER 00Z THURSDAY. LOW CLOUDS WILL ALSO
FILTER IN BEHIND THE FRONT...BUT CONFIDENCE IN SUB-VFR CEILINGS BY
06Z TOO LOW TO MAKE MENTION AT THIS TIME.
&&
PREV DISCUSSION... /ISSUED 320 PM CST TUE FEB 24 2015/
SHORT TERM...
AN UPPER LOW OVER ARIZONA EARLY THIS AFTERNOON REMAINS PROGGED TO
MOVE EWD ACROSS WEST TEXAS TONIGHT. MODELS ARE IN PRETTY GOOD
AGREEMENT IN SPLITTING SOME OF THE ENERGY IN THAT LOW...INITIALLY BY
THE DEVELOPMENT OF A NEW CLOSED FEATURE OVER NRN NEW MEXICO WHILE
BULK OF THE ENERGY ASSOCIATED WITH THE STRONG VORT MAX IN THE BASE
OF THE TROUGH AND A 130-PLUS KT JET AT 250 MB MOVES FROM SRN NEW
MEXICO ACROSS THE PERMIAN BASIN TO NORTH TEXAS. THIS LATTER STRONGER
FEATURE WILL FOCUS PRECIPITATION FROM THE SACRAMENTO...GUADALUPE AND
DAVIS RANGES EWD THROUGH THE PERMIAN BASIN AND SRN BIG COUNTRY...
POTENTIALLY CLIPPING THE EXTREME SRN PART OF THE FCST AREA...IN
GOOD AGREEMENT WITH THE PREVIOUS FCST. FURTHER NORTH UNDERNEATH
THE NEWLY- DEVELOPED NORTHERN EXTENSION OF THE LOW...SOME MID
LEVEL INSTABILITY COULD BE PRESENT WITH THE COOLER TEMPS
ALOFT...BUT MINIMIZED GIVEN NOCTURNAL TIMING. ANY PRECIP THAT IS
GENERATED WILL HAVE TO WORK THROUGH DRY SUB-CLOUD AIR FURTHER
LIMITING SFC PRECIP POTENTIAL. COULD SEE A FEW FLURRIES FURTHER
NORTH TOWARD THE SRN PANHANDLE... BUT EVEN THAT LOOKS SLIM. WILL
CONTINUE TO LIMIT SLIGHT CHC POPS TO THE SRN EXTREMITY OF THE FCST
AREA ATTM.
CLEARING SKIES...MODEST WEST WINDS...AND POSSIBILITY OF SOME
COMPRESSIONAL WARMING AHEAD OF COLD FRONT PROGGED TO ARRIVE LATE IN
THE DAY...ALL POINT TO A NICE...ALBEIT BRIEF...WARMUP. 12Z NAM-BASED
OBJECTIVE GUIDANCE COOLED DOWN QUITE A BIT FOR WEDNESDAYS HIGHS
COMPARED TO PREVIOUS RUNS. THIS MAY BE RELATED IN PART TO PERCEIVED
OVERABUNDANCE OF LOW LEVEL MOISTURE AND POSSIBLY STRATUS ACROSS THE
WRN HALF OF THE FCST AREA THROUGH HALF OF THE DAY. PREFER WARMER END
OF GUIDANCE BASED ON GFS AND TO A LESSER EXTENT THE ECMWF...AND NEAR
PREVIOUS FCST.
LONG TERM...
THE EXTENDED PERIODS ARE STILL EXPECTED TO REMAIN VERY ACTIVE WITH
A SERIES OF IMPULSES AND ANOTHER VERY COLD INTRUSION. THIS NEXT
PLUNGE OF ARCTIC AIR WILL BE SPREADING IN BY WEDNESDAY EVENING
WITH MOST SOLUTIONS TRENDING A BIT FASTER AND COLDER. THERE
APPEARS TO BE SOME POSSIBILITY FOR LOW LEVEL SATURATION JUST
BEHIND THE FRONT PERHAPS LEADING TO LIGHT SNOW SHOWERS AS THIS
FRONTAL BOUNDARY DROPS SOUTH EARLY THURSDAY...BUT DRY AIR ARRIVING
FROM THE CENTRAL PLAINS SHOULD MINIMIZE CHANCES FOR ANYTHING
SIGNIFICANT. A MOIST LAYER NEAR 700MB - 750MB LOOKS LIKE IT MAY
PERSIST ABOVE THE DRY LOWER LEVELS THROUGH MUCH OF OR ALL DAY
THURSDAY ESPECIALLY CENTRAL AND WESTERN AREAS. MID AND UPPER FLOW
WILL BACK LATE THURSDAY AHEAD OF ONE OF THE MODEST WAVES HELPING
TO CARVE OUT THE NEW WESTERN U.S. TROUGH...AND WILL EJECT OVER THE
AREA EARLY FRIDAY. ISENTROPIC UPGLIDE WILL DEVELOP THURSDAY NIGHT
IN THE 295K POTENTIAL TEMPERATURE LAYER NEAR 700 MB WITH
THICKENING MID LEVEL CLOUD LAYER AND SHOULD BEGIN PRECIPITATING
INTO THE DRIER AIR BELOW. HOW LONG IT TAKES TO SATURATE LOWER
LEVELS IS A SIGNIFICANT QUESTION...THOUGH MAJORITY OF SOLUTIONS DO
ALLOW FOR MOST PRECIPITATION SPREADING IN FROM THE WEST MAINLY A
LITTLE AFTER 06Z FRIDAY WITH TOTALS GENERALLY IN THE 0.20" TO
0.40" RANGE. WE FEEL THIS IS LIKELY OVERDONE THOUGH RETAINED OUR
NATIONAL GUIDANCE QPF CHARTS...WHILE CLIPPING PROJECTED SNOW
AMOUNTS IN THE GRIDS TO MOSTLY UNDER 4". THE AIRMASS BY EARLY
FRIDAY WILL BECOME VERY COLD...H850 MB TEMPERATURES PERHAPS AS LOW
AS -15 DEGREES CENTIGRADE...SO DRY SNOW RATIOS NEAR 17% SEEM
REASONABLE. ANYWAY...THIS CURRENTLY HAS THE APPEARANCE TO US OF A
ANOTHER ADVISORY-LEVEL EVENT. WE LOWERED TEMPERATURES ANOTHER
NOTCH OR TWO FROM THURSDAY THROUGH SATURDAY MORNING.
THIS IMPULSE WILL CLEAR TO THE EAST LATER FRIDAY WHILE LOWER
LEVELS WILL REMAIN COLD AND MOIST WITH UPSLOPE FLOW WHILE THE NEXT
LOW AMPLITUDE IMPULSE ALREADY WILL BE APPROACHING FRIDAY NIGHT AND
COULD RENEW LIGHT SNOW CHANCES INTO EARLY SATURDAY. LARGE SCALE
FEATURES APPEAR IN DECENT AGREEMENT FOR MID TO LATE WEEKEND WITH A
SHARP UPPER TROUGH CARVED OUT OVER THE SOUTHWEST THAT LIKELY WILL
CONTINUE TO SEND WEAK IMPULSES OUR WAY THROUGH THE SUB-TROPICAL
FLOW. HARD TO DISCOUNT MODEL PRECIPITATION DEPICTION THROUGH THE
WEEKEND ALTHOUGH LOWER LEVELS SHOULD GRADUALLY MODIFY AND BE
REPLACED BY AN AIRMASS WARM ENOUGH TO FAVOR MAINLY LIQUID. THIS
UPPER TROUGH EXPECTED TO EJECT BY LATE MONDAY AND EARLY TUESDAY
FINALLY ALLOWING SOMEWHAT COLDER AIR TO MOVE BACK TO THE
SOUTH...WHILE NEXT VERSION OF THE SOUTHWEST UPPER TROUGH WILL BE
TAKING PLACE WITH MORE LIGHT RAIN OR SNOW CHANCES MID WEEK.
THIS IS ALL ABNORMALLY ACTIVE AND INCREASINGLY COMPLEX. WE HAVE
NECESSARILY ATTEMPTED TO PUT HIGHEST RESOLUTION IN THE THURSDAY
AND FRIDAY FEATURES...AND ACKNOWLEDGE THAT MORE POSSIBLE SCENARIOS
BEYOND FRIDAY THAN ARE CURRENTLY INDICATED. RMCQUEEN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 40 20 54 25 / 10 10 0 40
TULIA 43 21 55 26 / 0 10 0 30
PLAINVIEW 44 23 58 28 / 0 10 0 30
LEVELLAND 45 24 61 29 / 0 10 0 20
LUBBOCK 47 25 61 29 / 0 10 0 20
DENVER CITY 45 27 61 30 / 0 20 0 10
BROWNFIELD 43 27 60 30 / 0 10 0 20
CHILDRESS 49 26 58 29 / 0 10 0 20
SPUR 45 27 60 31 / 0 10 0 10
ASPERMONT 42 30 58 32 / 0 20 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
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